What is open fetal surgery for CPAM?

Congenital pulmonary airway malformation (CPAM) is a growth in the lungs that may increase in size before the baby is born. Although most patients do not require prenatal intervention, larger masses can affect a baby’s heart function, and in severe cases this condition can lead to hydrops (a build-up of fluid in the body). Hydrops is a sign of heart failure and can trigger premature labor as well as mirror syndrome, when the mother develops preeclampsia-like symptoms in response to the fetal hydrops.

Steroid therapy can stop or slow the growth of some types of CPAMs and is usually tried as a first step if the baby is showing signs of heart failure. If the baby doesn’t respond to steroid therapy and the mass is fluid-filled, your doctor may use a needle to drain the mass and ease the strain on the baby’s body. A small tube called a shunt can also be placed while the baby is still in the womb to continue draining the mass in case the fluid returns.

In very rare cases, open fetal surgery to remove the abnormal lung tissue (a procedure called a fetal lobectomy) may be the only way to save the pregnancy. Babies later in gestation may undergo surgery using an ex utero intrapartum treatment (EXIT) procedure, which involves partially delivering the baby and keeping him or her attached to the placenta during the surgical removal of the CPAM.

Prenatal surgery is recommended only if your baby’s condition is deemed life-threatening; otherwise it is recommended that surgery wait until shortly after birth. This surgical option is available at only the most specialized centers, including the Fetal Concerns Center at Children’s Wisconsin.

During the procedure, the mother and baby are asleep under general anesthesia and given medications for pain control. The operating room team includes multidisciplinary experts dedicated to caring for mom and baby: maternal fetal medicine specialists, the fetal surgeon who removes the mass, a pediatric cardiologist who monitors the baby’s heartbeats, and anesthesiologists for both the baby and mother.

After making the incision in the mother, the surgeon opens the uterus away from placenta to expose the baby’s chest. Keeping the baby in the womb, the medical team infuses warm fluids into the uterus to keep amniotic fluids normal, allowing the fetus and umbilical cord to continue to float and remain safe. The surgeon removes the affected lobe of the lung and then closes the opening in the baby’s chest. After the baby’s surgery is complete, the surgeon then closes the mom’s uterus and abdominal incision. Mother and baby are also given antibiotics to prevent infection. The entire procedure takes approximately two hours.

Candidates for in-utero CPAM surgery

Not every baby with CPAM is a candidate for this surgery. For safety’s sake, patients must meet the following criteria:

• There must be a compelling reason for fetal intervention (such as life-threatening complications).
• The mother must not show symptoms of mirror syndrome.
• The surgery must be done within a certain time period in the pregnancy — between 19-28 weeks.
• The baby must not have a genetic problem or any other major birth defect.
• The mother must be pregnant with only one baby.
• The mother must not have any one of a number of health conditions.

While prenatal surgery offers potential benefits, it also carries risks for both the mother and the baby, including an increased likelihood of premature labor. The specialists at the Fetal Concerns Center will help you decide whether prenatal surgery is the right option for you and your baby.

How does in-utero CPAM surgery affect my baby?

If the tumor is large, it can compress the heart and limit the heart’s ability to function properly. Removing most or all of the tumor allows the heart to work normally and potentially resolves the hydrops, allowing your baby’s body to continue developing in the womb as long as possible.

How does open fetal surgery for CPAM affect the pregnancy?

To decrease the risk of preterm delivery, you will need to remain on modified bed rest after the surgery. You will be closely monitored for the rest of your pregnancy, and you will need to deliver your baby via a scheduled Cesarean section at 37 weeks, unless you go into labor earlier, at the Froedtert & the Medical College of Wisconsin Birth Center.

What happens after surgery?

You will remain in the hospital for 4-5 days after the prenatal surgery.

What about after birth?

Your baby will receive top-notch care in Children’s Wisconsin’s Level IV Neonatal Intensive Care Unit, which is ranked as one of the best in the nation.

Will I be able to help care for my baby?

Absolutely. Our recently expanded and redesigned NICU was created to promote family bonding, with private rooms where parents can stay with their baby 24/7, and other special features for families’ comfort. Our on-call lactation specialists can help you successfully breastfeed and pump and store breast milk when direct breastfeeding isn’t an option.

When can my baby go home?

Your baby will be discharged from the hospital once he or she is breathing independently, eating well and gaining weight. That may take several weeks.

What’s my baby’s long-term prognosis?

Survival rates for babies with hydrops who undergo open fetal surgery for CPAM are about 50 percent. Babies who survive until birth have very good outcomes. After the mass is removed, children usually have normal lung function eventually.

What about future pregnancies?